Glycine

Glycine (CAS 56-40-6), abbreviated Gly and designated E640, is the simplest amino acid and a high-volume industrial ingredient.

Where is Glycine used?

• Pharmaceuticals: buffering agent in parenteral formulations and stabilizer in lyophilized protein and vaccine products
• Food: flavor modifier and mild sweetness enhancer in seasonings and processed foods
• Beverages: regulatory designation supports EU-compliant labeling
• Personal care: improves moisture retention in skin creams, serums, and hair care products
• Chemical synthesis: intermediate in the synthesis of active pharmaceutical ingredients, agrochemicals, and chelating agents such as glyphosate and EDTA derivatives
• It functions as a pH buffer, humectant, and flavor modifier.
• Used in media, sera and cell supplements.
• Included as a component of some urological irrigation solutions and oral nutrition products.
• Used in sports products, functional foods, amino acid complexes and various special formulations.

Formulation notes

• High concentrations administered via irrigation solutions require monitoring of serum electrolytes and osmolality.

Typical specification

• Assay (perchloric acid titration, calculated on dried basis) is 99.0–101.0%.
• Loss on drying at 105°C is at most 0.2%.
• Residue on ignition (as sulfate) is at most 0.1%.
• High water solubility allows the preparation of high-concentration solutions, but pH control may be required to maintain compatibility with other formulation components.

Regulatory status

• In the EU, glycine and its sodium salt are permitted as food additive E 640 without a maximum quantity limit.
• Customs code for Glycine is 2922498590.

Storage, packaging and handling

• Recommended to store in a cool, dry place away from direct sunlight with the packaging closed.
• The solid form is chemically stable and generally easy to handle, but sterile processing is required for injection and irrigation uses.

Frequently asked questions about Glycine

What are the limits for ninhydrin-positive substances?

Each individual ninhydrin-positive substance is at most 0.10%, and the total is at most 1.0%.

How does glycine behave at different pH values?

It is an amphoteric ion and dissociates on both the acidic and basic sides; it becomes an ammonium cation at pH below 2.4 and a glycinate at pH above 9.6.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.